青海藏羊血清运铁蛋白多态性的研究

采用聚丙烯酰胺凝胶电泳法对青海省三角城种羊场和达日县的１９６份藏羊血样进行了血清运铁蛋白多态性的研究。结果发现：①在被检藏羊的血清运铁蛋白位点上共发现ＴＦ￣Ｉ，ＴＦ￣Ａ，ＴＦ￣Ｇ，ＴＦ￣Ｂ，ＴＦ￣Ｌ，ＴＦ￣Ｃ，ＴＦ￣Ｄ，ＴＦ￣Ｍ，ＴＦ￣Ｅ，ＴＦ￣Ｑ和ＴＦ￣Ｐ１１个等位基因，其中ＴＦＣ（０．３２４０），ＴＦ￣Ｂ（０．２６７９）和ＴＦ￣Ｄ（０．２１６８）为优势等位基因；②共发现ＴＦＩＥ，ＴＦＡＡ，ＴＦＡＢ，ＴＦＡＣ，ＴＦＡＤ，ＴＦＡＭ，ＴＦＧＢ，ＴＦＧＬ，ＴＦＧＣ，ＴＦＧＤ，ＴＦＢＢ，ＴＦＢＣ，ＴＦＢＤ，ＴＦＢＭ，ＴＦＬＣ，ＴＦＬＤ，ＴＦＬＥ，ＴＦＣＣ，ＴＦＣＤ，ＴＦＣＥ，ＴＦＣＱ，ＴＦＣＰ，ＴＦＤＤ，ＴＦＤＭ，ＴＦＤＥ和ＴＦＤＱ２６种基因型，其中ＴＦＢＣ（２０．４１％）、ＴＦＣＣ（１３．７８％）和ＴＦＢＤ（１１．７４％）为优势基因型。     

异源抗原在建立ELISA检测传染性法氏囊病毒抗体中的应用

本文报告采用ｖｅｒｏ细胞增殖的ＩＢＤＶ抗原建立了间接酶联免疫吸附试验（ＥＬＩＳＡ），用于定量检测鸡传染性法氏囊病毒（ＩＢＤＶ）抗体。该法快速、敏感性高、特异性强、重复性好。同时，通过３０份血清样品ＥＬＩＳＡ效价（ＥＴ）的对数值（ｌｏｇＥＴ）与血清Ｐ／Ｎ值（待检血清ＯＤ值与阴性血清ＯＤ值之比）的线性回归分析，得直线方程ｙ＝３．０５８９＋０．０７３９ｘ（ｒ＝０．９１７４），从而血清样品的ＥＴ可通过血清单一稀释度的Ｐ／Ｎ值来计算。用不同来源抗原作ＥＬＩＳＡ表明，从ｖｅｒｏ细胞增殖的抗原比从鸡胚成纤维（ＣＥＦ）细胞增殖的抗原可提高检测血清ＯＤ值近２０％，表现出异源抗原具有更高的特异性     

不同大豆加工产品对早期断奶仔猪饲用价值的研究

２１日龄平均体重的５．８５ｋｇ的断奶仔猪３２头,按随机区组设计分２组,分别饲喂豆粕（ＳＢＭ）和膨化全脂大豆（ＥＦＳ）型日粮。试验结果表明：０～１４ｄ间,ＳＢＭ组平均日增重（ＡＤＧ）和平均日采食量（ＡＤＦＩ）分别比ＥＦＳ组显著提高４５．９％和２５．８％（Ｐ〈０．０５）;１５～２８ｄ间,ＳＢＭ组ＡＤＧ比ＥＦＳ组显著提高７．７％（Ｐ〈０．０５）。全期试验（０～２８ｄ）ＳＢＭ组ＡＤＧ和ＡＤＦＩ分别比ＥＦＳ     

鸡传染性贫血病对雏鸡新城疫疫苗免疫的抑制机理──Ⅰ．细胞因子的变化

１日龄健康ＡＡ雏鸡感染ＣＩＡＶ后８天进行ＮＤ疫苗免疫，免疫后２９天用ｖＮＤＶ攻击，于免疫后７、１４、２８和攻毒后１０天取材检测．给果，感染ＣＩＡＶ雏鸡经ＮＤ免疫后７天，胸腺Ｔ细胞白细胞介素２（ＩＬ－２）诱生活性比未感染的免疫对照鸡明显降低（Ｐ＜０．０１）；脾脏Ｔ细胞ＩＬ－２诱生活性于７和２８天显著降低（Ｐ＜０．０５，Ｐ＜０．０１）．感染免疫鸡免疫后１４天脾脏淋巴细胞干扰素（ＩＦＮ）诱生活性明显降低（Ｐ＜０．０１）．结果表明感染ＣＩＡＶ鸡对ＮＤ疫苗免疫的分子免疫调节作用明显减弱，ＨＩ抗体效价于免疫后７～２８日明显降低（Ｐ＜０．０５）。ＮＤ强毒攻击后，ＣＩＡＶ感染ＮＤ免疫雏鸡的免疫保护率为６０％％，明显低于免疫对照鸡（１００％）．     

犬瘟热病毒抗体检测方法的比较研究

用犬瘟热（ＣＤ）弱毒和自制的高免犬血清，建立了检测犬瘟热病毒（ＣＤＶ）抗体的中和（ＳＮ）试验、间接荧光抗体技术（ＩＦＡＴ）和间接免疫酶染色法。这３种方法对３８份ＣＤ弱毒疫苗免疫犬血清抗体效价的测定结果表明，当被检血清稀释度为１∶１００时，ＳＮ试验、ＩＦＡＴ和间接免疫酶染色法测定时的阳性血清数分别为２９，７和３１份，ＩＦＡＴ和间接免疫酶染色法测定结果相对于ＳＮ试验结果的符合率分别为４２．１％和９４．７％。同时发现，当ＳＮ试验测定的血清效价在１∶１００以上时，ＩＦＡＴ测定结果总是在１∶２５以上，间接免疫酶染色法测定结果总是在１∶１００以上。３种方法以各自初步确定的ＣＤＶ血清抗体效价完全保护值指标计算所测血清的完全保护率，ＳＮ试验为７６．３％，ＩＦＡＴ为７８．９％，间接免疫酶染色法为８１．６％。据此认为，ＩＦＡＴ和间接免疫酶染色法均可部分代替ＳＮ试验用于ＣＤ疫苗免疫效果的评价、免疫犬抗体水平的监测以及ＣＤ的流行病学调查     

鸡传染性贫血病对雏鸡新城疫疫苗免疫的抑制机理：Ⅰ.细胞因子的变化

１日龄健康ＡＡ雏鸡感染ＣＩＡＶ后８天进行ＮＤ疫苗免疫，免疫后２９天用ｖＮＤＶ攻击，于免疫后７，１４，２８免疫后７天，胸腺Ｔ细胞白细胞介素２（ＩＬ－２）诱生活性比未感染的免疫对照鸡显降低（Ｐ＜０．０１）；脾脏Ｔ细胞ＩＬ－２诱生活性于７和２８天著降低（Ｐ＜０．０５，Ｐ＜０．０１）。感染免疫鸡免疫后１４天脾脏淋巴细胞干扰素（ＩＦＮ）诱生活发性明显降低（Ｐ＜０．０１）。结果表明感染ＣＩＡＶ鸡对ＮＤ疫苗免疫     

日粮烟酸水平对肉鸭后期生产性能和脂肪代谢的影响

７２只２１日龄樱桃谷鸭平均分成４组,分别添加０、３０、６０、９０ｍｇ／ｋｇ烟酸进行３周饲养试验。测定平均日采食量（ＡＤＦＩ）、平均日增重（ＡＤＧ）、料重比（Ｆ／Ｇ）、血清总胆固醇（ＴＣＨ）、血清总甘油三酯（ＴＧ）、低密度脂蛋白胆固醇（ＬＤＬ－Ｃ）、高密度脂蛋白胆固醇（ＨＤＬ－Ｃ）。结果表明：①日粮烟酸水平不影响ＡＤＦＩ、ＡＤＧ、Ｆ／Ｇ（Ｐ＞０．０５）,但与ＡＤＦＩ、ＡＤＧ、Ｆ／Ｇ存在显著（Ｐ＜０．０５）或极显著二次曲线关系（Ｐ＜０．０１）。②日粮烟酸水平可能影响ＴＣＨ、ＴＧ、ＬＤＬ－Ｃ、ＨＤＬ－Ｃ,但差异不显著（Ｐ＞０．０５）。当基础日粮烟酸和色氨酸水平分别为３５ｍｇ／ｋｇ和０．１６％时,建议肉鸭后期烟酸添加水平为６０ｍｇ／ｋｇ。     

青海细毛羊血清运铁蛋白多态性的研究

采用聚丙烯酰胺凝胶电泳法对４０１只青海细毛羊的血清运铁蛋白多态性进行了研究。结果表明：①青海细毛羊血清运铁蛋白座位上有ＴＦＡ，ＴＦＧ，ＴＦＢ，ＴＦＣ，ＴＦＤ，ＴＦＭ，ＴＦＥ和ＴＦＱ８个等位基因，其中ＴＦＣ（０．３８７８）和ＴＦＡ（０．２４９４）为优势等位基因；②已发现ＴＦＡＡ，ＴＦＡＧ，ＴＦＡＢ，ＴＦＡＣ，ＴＦＡＤ，ＴＦＡＭ，ＴＦＡＥ，ＴＦＡＱ，ＴＦＧＧ，ＴＦＧＢ，ＴＦＧＣ，ＴＦＧＤ，ＴＦＢＢ，ＴＦＢＣ，ＴＦＢＤ，ＴＦＢＭ，ＴＦＣＣ，ＴＦＣＤ，ＴＦＣＭ，ＴＦＣＱ，ＴＦＤＤ，ＴＦＤＭ，ＴＦＤＥ２３种基因型，以ＴＦＡＣ（２０．９５％）的出现频率最高；③ＴＦ座位的基因杂合度为０．７３８１；④在公羊组和母羊组，ＴＦ基因型与体重、毛长和产毛量之间无显著性联系。     

鸡传染性贫血病对雏鸡新城疫疫苗免疫的抑制机理──Ⅱ．T、B细胞功能变化

１日龄健康雏鸡感染ＣＩＡＶ后８天进行ＮＤ疫苗免疫和免疫后２９天用ｖＮＤＶ攻击，于免疫后７、１４、２８天和攻毒后１０天取材检测。结果，感染ＣＩＡＶ雏鸡ＮＤ免疫后，胸腺和脾脏Ｔ细胞增殖反应分别于７天和７～１４天比未感染免疫对照鸡明显减弱（Ｐ＜０．０１，Ｐ＜０．０５）法氏囊和脾脏Ｂ细胞增殖反应均于７～１４天明显减弱（Ｐ＜０．０５，Ｐ＜０．０１）。ｖＮＤＶ攻击后，脾脏和胸腺Ｔ细胞增殖反应均比未感染ＣＩＡＶ的免疫对照鸡显著降低（Ｐ＜０．０１．Ｐ＜０．０５）。上述结果表明，ＣＩＡＶ感染ＮＤ免疫雏鸡中枢和外周免疫器官的细胞免疫应答和体液免疫应答功能均明显降低，并与其分子免疫调节功能降低密切相关。     

鸡传染性贫血病对雏鸡新城疫疫苗免疫的抑制机理Ⅱ.T,B细胞功能变化

１日龄健康雏鸡感染ＣＩＡＶ后８天进行ＮＤ疫苗免疫和免疫后２９天用ｖＮＤＶ攻击，于免疫后７、１４、２８天和攻毒后１０天取材检测。结果，感染ＣＩＡＶ雏鸡ＮＤ免疫后，胸腺和脾脏Ｔ细胞增殖反应分别于７天和７－１４天比未感染免疫对照鸡明显减弱（Ｐ＜０．０１，Ｐ＜０．０５）法氏囊和脾脏Ｂ细胞增殖反应均于７－１４天明显减弱（Ｐ＜０．０５，Ｐ＜０．０１）。ｖＮＤＶ攻击后，脾脏和胸腺Ｔ细胞增殖反应均比未感染ＣＩＡＶ     

Serologic prevalence of Toxoplasma gondii in horses slaughtered for food in North America.

Serum samples from 1788 horses slaughtered for food in North America were tested for antibodies to Toxoplasma gondii using the modified direct agglutination test (MAT). Antibodies to T. gondii were found by the MAT in 124 (6.9%) of 1788 sera; the titers were 1:20 (69 horses), 1:40 (37 horses), 1:80 (9 horses), and > or =1:160 (9 horses). A total of 339 selected horses were also tested by the Sabin-Feldman dye test (DT). Dye test antibodies were found in 54 horses with titers of 1:10 (29 horses) 1:20 (12 horses), 1:40 (4 horses) and 1:80 (9 horses). There was no correlation between the DT and the MAT.     

Prevalence of agglutinating antibodies to Toxoplasma gondii in small ruminants of the Madrid region,Spain, and identification of factors influencing seropositivity by multivariate analysis

A seroepidemiological survey of Toxoplasma gondii infection in sheep and goats was conducted in the Madrid region of Spain. Sera were collected from 60 herds, for which farming management information and other relevant data for their characterization were also obtained through a questionnaire. The seroprevalence was 11.8% (64 out of 541), using the modified (2-mercaptoethanol) direct agglutination technique with a 1:64 cut-off titre. The relationship between seropositivity and the variables in the questionnaire was assessed by multivariate analysis. Four variables were found to be significantly associated with seroprevalence. Two of them, the presence of cats and a previous history of abortion outbreaks in the farm, were factors known to be linked with toxoplasmosis, indicating the validity of the serological data. Seropositivity was also related to a lack of replacements in the preceding year. Proximity to other farms appeared to be a protective factor negatively associated with seropositivity, probably because it was an indicator of proximity to an urban area and the availability of local sanitary facilities.Abbreviations AIDS acquired immune deficiency syndrome - logistic regression coefficient - CI confidence interval - MDAT modified direct agglutination test - OR odds ratio - p level of significance - SE standard error     

The relationship between the microtitration serum agglutination and complement fixation tests in bovine brucellosis serology

The relationship between antibody titres in the microtitration serum agglutination test and the complement fixation test in bovine brucellosis is described. For low and high MSAT values there is good agreement between the 2 tests. This is not the case for MSAT values between 54 and 338 IU/ml. For practical reasons, results falling into this category cannot all be repeated. Repetitions are so structured that less than 4% of the tests need to be repeated. If the level of repetitions should show an increase above 4%, it is assumed that technical or human error has occurred.     

Sensitivity and specificity of various serological tests for the detection of Toxoplasma gondii infection in naturally infected sheep

Comparative serological examination of 300 serum samples from sheep slaughtered in the main abattoir in Cairo, Egypt revealed a higher prevalence of toxoplasmosis (43.7%) with the modified agglutination test (MAT), followed by the enzyme linked immune-sorbant assay (ELISA) (41.7%) and the indirect fluorescent antibody test (IFAT) (37%), while the lowest prevalence was detected with the dye test (DT) (34%). When the data from the first three serological tests were compared with that of the DT test, which was used as a reference test for toxoplasmosis, MAT had the highest sensitivity (96%), followed by ELISA (90.1%) and IFAT, which demonstrated the lowest sensitivity (80.4%). Conversely, IFAT had the highest specificity (91.4%), followed by MAT (88.9%) and ELISA (85.9%).     

Evaluation of an enzyme-labeled antiglobulin test for anti-Brucella immunoglobulin G among 3 cattle populations

Antibody to smooth Brucella abortus lipopolysaccharide antigen on the surface of polystyrene tubes was detected with peroxidase-labeled antibody against bovine immunoglobulin G. The enzyme-labeled antiglobulin test (ELAT) activity of samples was expressed in arbitrary units/0.01 ml by reference to a standard curve based on tests of dilutions of a positive serum pool. Reactions greater than 3.0 U/0.01 ml were classified positive because specificity at this level was 99.8% (417/418 samples correctly classified negative) with agglutination test-negative sera from 33 Brucella-free herds. Results of the ELAT were compared with results of agglutination tests and the complement-fixation test (CFT), using 430 sera from cattle in 7 infected herds. Activity of greater than 5.0 ELAT U/0.01 ml was detected in all 54 sera classified as positive (titer greater than 1:10) by the CFT, including 5 sera classified as negative by the tube agglutination test. Sera from 8 nonvaccinated cows in the infected herds reacted only by the ELAT, whereas reactions were obtained with 25 and 5 sera by only agglutination tests and the CFT, respectively. The ELAT and CFT results were in agreement for 25 of 26 sera from agglutination test-reactor cattle in herds of unknown status. Comparisons of milk ring and whey agglutination tests with the whey ELAT on 146 quarter samples from cows in an infected herd revealed no ELAT activity greater than or equal to 1.0 U/0.01 ml in the 73 samples considered negative by the 2 other tests. Samples (n = 47) that contained greater than or equal to 1.0 ELAT U/0.01 ml included all (n = 40) samples with milk ring or whey agglutination titers greater than or equal to 1:16 and greater than or equal to 32, respectively, and 7 samples that gave weaker reactions to the latter tests.     

Serologic evaluation of cattle inoculated with Toxoplasma gondii: comparison of Sabin-Feldman dye test and other agglutination tests

Six cows and 6 calves were each inoculated with 100 or 100,000 Toxoplasma gondii oocysts. Serum samples were analyzed, using the Sabin-Feldman dye test (DT), indirect hemagglutination test, latex agglutination test, and the modified direct agglutination test (MAT). Antibody titers in cows were lower than in calves. In the cows, DT titers increased briefly during the first month after inoculation, after which the titers were negative; however, T gondii was isolated from the tissues of 4 cows. Indirect hemagglutination and latex agglutination titers were generally less than 1:256. The MAT titers increased to 1:1,024 during the first month after inoculation. In 5 of the 6 cows, the MAT titers persisted. The 6th cow had a preinoculation MAT titer of 1:2,000 for 3 to 6 months. Therefore, the DT was not useful in serologic surveys for T gondii in cattle; the MAT was the most sensitive test and may be useful in the diagnosis of T gondii infection in cattle.     

Direct agglutination test for Encephalitozoon cuniculi

Encephalitozoon cuniculi is a small protozoan parasite in the phylum Microspora. It has been shown to naturally infect several host species, including humans. Infection with microsporidia is usually asymptomatic, except in young or immunocompromised hosts. Currently, serological diagnosis of infection is made using the indirect immunofluorescent antibody assay (IFA) or enzyme-linked immunosorbent assay (ELISA). Although these methods are sensitive and reliable, there are several drawbacks to the IFA and ELISA tests. Cross-reactivity between other Encephalitozoon species is common, and specialized equipment is required to conduct these tests. This paper reports the development of a direct agglutination test for detecting IgG antibodies to E. cuniculi. The utility of the agglutination test was examined in CD-1 and C3H/He mice infected with E. cuniculi or one of 2 other Encephalitozoon species. Test sera were incubated overnight with eosin-stained microsporidia spores in round-bottom microtiter plates. In positive samples, agglutination of spores with antibodies in test sera resulted in an opaque mat spread across the well. The results indicate that the agglutination test is 86% sensitive and 98% specific for E. cuniculi, with limited cross-reactivity to Encephalitozoon intestinalis. No cross-reactivity to Encephalitozoon hellem was observed. The test is fast and easy to conduct, and species-specific antibodies are not required.     

Field trial of six serological tests for bovine brucellosis

Serum agglutination (SAT), complement fixation (CFT), indirect ELISA (iELISA), competitive ELISA (cELISA), Rose Bengal (RBT) and EDTA-modified agglutination (EDTA) tests were used in parallel on serological samples from 19,935 cattle in 301 herds. The study herds were selected according to putative exposure to Brucellaabortus with cases defined by bacteriological culture or test agreement. No single test identified all infected cattle and, at diagnostic thresholds, relative sensitivity was highest in the iELISA (67.9%) or RBT (78.1%), using bacteriological culture or test agreement, respectively, to define cases. As screening tests, the relative sensitivity of the SAT was highest (75.9% by culture or 84.9% by test agreement), with an optimal threshold of 31 IU. The relative specificity of the diagnostic tests ranged from 99.6% (SAT 31IU) to 100% (iELISA, RBT and CFT). The trial confirmed the value of the SAT as a screening test and the value of parallel testing.     

The influence of feeding and maintenance system on occurrence of Toxoplasma gondii infections in dogs

Serum samples of 113 dogs visiting "outpatient clinics", 52 dogs kept in shelters and 35 animals from a military dog training centre were examined for Toxoplasma gondii specific antibodies using a latex agglutination test. Significant differences in seroprevalences were found between dogs from the training centre (8.6% of positive results) and the other populations examined (40.7% of positive seroreagents in animals visiting outpatient clinics and 44.2% in the group from shelters, respectively). Among clinic patients, dogs fed raw meat were significantly more frequently seropositive (65.2%) than those eating only commercial dry feed or cooked meat (25.7%). No statistically significant differences were noted in males compared to females and in pure breed dogs compared to crossbreed dogs. The antibodies were usually found in low titres under 60 IU/ml (69.6% of positive results). High titres (120-480 IU/ml) were detected in 2 of 3 dogs with clinical toxoplasmosis. In these dogs IFAT T. gondii specific IgM were detected and a favourable response to antiprotozoal treatment was observed. All the dogs with medium and high titres were given raw meat. Age and the presence of cats did not seem to have any influence on T. gondii seroprevalence. Neospora caninum specific antibodies in low titres ranging from 1:20-1:320 were found in 7 (9.7%) of 72 T. gondii positive seroreagents.     

Concurrent Infection with Toxoplasma gondii and Feline Leukemia Virus: Antibody Response and Oocyst Production

Four adult cats (two testing positive and two negative for feline leukemia virus FeLV) were fed Toxoplasma gondii tissue cysts collected from the brains of mice. Two control cats (1 FeLV+, 1 FeLV-) were not fed cysts. The cats infected with T. gondii shed thousands of oocysts but remained clinically and physically normal, with hemograms and clinical chemistry values essentially unchanged irrespective of their FeLV status. Infection with FeLV did not increase the duration of oocyst shedding. At necropsy no significant lesions were found. T. gondii antibodies were detected by three serologic tests in the cats fed tissue cysts. The time necessary for an antibody response to T. gondii was not altered by the FeLV infection. Indirect hemagglutination (IHA) was the least reliable of the serologic tests studied; it detected antibodies later in the infection, and titers were less than in the other tests. Latex agglutination (LA) detected antibodies a few days before IHA, but titers were less than in modified direct agglutination (MAT). MAT detected antibodies earliest in the infection and also measured antibodies in aqueous humor and cerebrospinal fluid.